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[SCWCD] Difference between ${request} and ${requestScope}

Paulo Gervásio.

Joined: Aug 14, 2010
Posts: 12

I have a doubt with these parameters included in EL.

I thought that ${requestScope} contained a map with the request attributes and the ${request} object was exactly a HttpServletRequest "javaBean".
But using the ${request} object, I couldn't get the others objects in this object like getServerPort(), getContextPath() etc... (I just can do it using ${pageContext.request.serverPort}, for example).

And now I have this doubt... What's the difference between ${request} and ${requestScope}? Are they equals?

Paulo Gervásio

Mark Uppeteer
Ranch Hand

Joined: Mar 02, 2004
Posts: 159

Hi Paulo,

there is no request object in EL. On requestScope your view is right.

in EL you have to use pageContext to get to your request object.
PageContext is the only non map like object.
So ${pageContext.request} is what you need.


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Frits Walraven
Creator of Enthuware JWS+ V6
Saloon Keeper

Joined: Apr 07, 2010
Posts: 2043

Hi Paulo,

What's the difference between ${request} and ${requestScope}? Are they equals?

In EL you have different implicit objects then for a JSP.

Have a look at my notes (SCWCD notes) and read chapter 7.11.10 and compare it with chapter 6.3.


[EDIT: Mark, you beat me there....]
Paulo Gervásio.

Joined: Aug 14, 2010
Posts: 12
Excuse me, but I can't understand the difference between the parameters....

I wanna know which method there are in one that there aren't in other....

Paulo Gervásio.

Joined: Aug 14, 2010
Posts: 12
I find the answer here

Thanks for help!

Bear Bibeault
Author and ninkuma

Joined: Jan 10, 2002
Posts: 63548

Here it is in plainer language: ${request} does not exist!

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Alx Tabanas

Joined: Jan 20, 2011
Posts: 2


In Servlet:
request.setAttribute("person", new Person("John Ba"));

Now what is exactly the differnece between:

${} and ${}

FYI: output is the same

Piotr Nowicki
Ranch Hand

Joined: Jul 13, 2010
Posts: 610

Hi Alx,

${} prints the same because the ${attributeName} looks for attributeName in all scopes. It starts with page scope, then request, then session and then application.
In your case, it can't find "person" in page scope, so it then looks for the request sope. It founds it there and prints it, so the result is the same.

Try setting "person" attribute i.e. in both - request and application scope in servlet. The ${} will print just the request scope one.

Vijitha Kumara

Joined: Mar 24, 2008
Posts: 3900

And Welcome to CodeRanch, Alx Tabanas

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Alx Tabanas

Joined: Jan 20, 2011
Posts: 2

big thanks

I agree. Here's the link:
subject: [SCWCD] Difference between ${request} and ${requestScope}
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